Ultra-thin miniature pump

ABSTRACT

An ultra-thin miniature pump applied to transport a fluid includes a main body, a rotor, and a stator. The main body includes a cover part and a bottom part. A joint surface between the cover part and the bottom part possesses an anti-leakage device, and a chamber including a suction port and a discharge port is formed inside the main body. The rotor disposed in the chamber includes a magnet set, an impeller, and a central shaft. The magnet set is connected on the surface of the impeller, and the impeller with the magnet set is aligned by the central shaft and rotates in coaxial. The stator disposed in the chamber includes a plurality of coils corresponding to the magnet set axially. The coils and the magnet set generate an axial magnetic flux to make the impeller rotate for transporting the fluid from the suction port to the discharge port.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to an ultra-thin miniature pump,especially for an ultra-thin miniature pump, which utilizes a design ofaxial-flux micromotor and possesses advantages of structureminiaturization, high rotating torque, high head rise, and excellentheat dissipation capability.

2. Related Art

Miniature pumps are very important units which are employed in variousfields such as liquid cooling systems, transporting devices of fuelcells, and artificial hearts. Therefore, it is a general objective ofdesigners and manufacturers to design and manufacture the miniaturepumps which include advantages of good anti-leakage capability, highrotating torque, high head rise, excellent heat dissipation capability,and structure miniaturization.

A centrifugal pump mainly includes coils of a stator, magnets of arotor, and an impeller. The centrifugal pump utilizes the flow ofelectric currents in the coils of the stator to create magnetic fields.Then, the magnetic fields act upon the magnets of the rotor to generatea magnetic force, and the impeller is rotated by the magnetic force totransport fluids. According to various motor disposing types of thepumps, the pumps could be divided into external motor pumps and internalmotor pumps. The external motor pumps and the internal motor pump aredescribed respectively as following:

-   -   a. The external motor pump has some features that its motor and        pump are split and a transmission shaft between the motor and        the pump is utilized to transmit motive force. There are        advantages of the external motor pump that the external motor        pump is easy to be assembled and the pump has a low leakage        rate. However, due to the longer transmission shaft between the        pump and the motor, the external motor pump would need bigger        space for assembling. Moreover, it is more difficult to align a        shaft of the pump with a shaft of the motor. If the shaft of the        pump is not aligned with the shaft of the motor, the external        motor pump will generate more vibratile noise and has a shorter        lifetime.    -   b. The internal motor pump has a feature that its motor is        disposed inside the pump and located in the center of an        impeller. Since a diameter of the motor is restricted with the        shape of vanes of the impeller, rotating torsion of the motor        will be constricted. If the diameter of the motor is increased,        the size of the vanes will be constricted and the flow rate or        output flow pressure will be limited. Moreover, since the motor        is located in the center of the impeller, heat of the motor is        difficult to dissipate and a lifetime of the motor will be        influenced.

Accordingly, the miniature pumps of the prior art mostly belong to theinternal motor pumps for reasons of structure miniaturization and littlevibratile noise. However, the miniature pumps of the prior -art, whichare disclosed by Taiwan Patent Issued No. 00587784, M321653 and UnitedStates Patent Issued No. 20030072656A1, generally adopt a design ofradial-flux motor and they are hard to avoid some drawbacks of lowrotating torque as well as low head rise and poor heat dissipationcapability of their motors. The above drawbacks are difficult problemswhat the people of the related fields want to solve.

SUMMARY OF THE INVENTION

In view of the above problems, an object of the present invention is toprovide an ultra-thin miniature pump to solve drawbacks of miniaturepumps of the prior art, such as low rotating torque, low head rise andpoor heat dissipation capability of pumps, and achieve structureminiaturization.

According to one embodiment of the present invention, an ultra-thinminiature pump is provided. The ultra-thin miniature pump of the presentinvention is applied to transport a fluid and comprises a main body, arotor, and a stator. The main body includes a cover part and a bottompart. A joint surface between the cover part and the bottom partpossesses an anti-leakage device, and a chamber including a suction portand a discharge port is formed inside the main body. The rotor disposedin the chamber includes a magnet set, an impeller, and a central shaft.The magnet set is connected on a surface of the impeller, and theimpeller with the magnet set is aligned by the central shaft and rotatesin coaxial manner. The stator disposed in the chamber includes aplurality of coils corresponding to the magnet set axially. The coilsand the magnet set generate an axial magnetic flux to make the impellerrotate for transporting the fluid from the suction port to the dischargeport. A sealing layer seals the stator, and the fluid and the coil areisolated by this sealing layer.

According to another embodiment of the present invention, an ultra-thinminiature pump is provided. The ultra-thin miniature pump of the presentinvention is applied to transport a fluid and comprises a main body, arotor, a stator, and a sealing layer. The main body includes a coverpart, a body part, and a bottom part combined in sequence. A jointsurface between the cover part and the body part possesses ananti-leakage device, and a chamber including a suction port and adischarge port is formed inside the main body. The rotor disposed in thechamber includes a magnet set, an impeller, and a central shaft. Themagnet set is connected on a surface of the impeller, and the impellerand the magnet set are aligned by the central shaft and rotate incoaxial manner. The stator disposed in the chamber of the body part andthe bottom part includes a plurality of coils corresponding to themagnet set axially. The coils and the magnet set generate an axialmagnetic flux to make the impeller rotate for transporting the fluidfrom the suction port to the discharge port. The sealing layer locatedin a portion of the chamber of the body part and the bottom part sealsthe coils and prevents the fluid from leaking through a joint surfacebetween the body part and the bottom part.

The ultra-thin miniature pump of the present invention utilizes a designof axial-flux micromotor. Since the magnet set is integrated with theimpeller and the coils are axially aligned with the magnet set, theultra-thin miniature pump of the present invention is light in weightand compact in size. Furthermore, since the magnet set is designedaccording to the shape of impeller of vortex pumps, there is more spacefor a motor of the ultra-thin miniature pump to increase its diameterand then the rotating torque and the head rise of the pump are promoted.Moreover, since the motor has larger dissipation space, it will preventthe motor from overheating and increase the lifetime of the motor.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given herein below for illustration only, and whichthus is not limitative of the present invention, and wherein:

FIG. 1 is a schematic diagram of an ultra-thin miniature pump accordingto a first exemplary embodiment of the present invention;

FIG. 2 is an exploded diagram of the ultra-thin miniature pump accordingto the first exemplary embodiment of the present invention; and

FIG. 3 is an exploded diagram of an ultra-thin miniature pump accordingto a second exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The features and practice of the present invention will be illustratedbelow in detail through preferred embodiments with reference to theaccompanying drawings.

Referring to FIG. 1, FIG. 1 illustrates a schematic diagram of anultra-thin miniature pump according to a first exemplary embodiment ofthe present invention. As shown in FIG. 1, an ultra-thin miniature pump10 according to a first exemplary embodiment of the present invention isutilized to transport a fluid (not shown in FIG. 1). The fluid could becoolant of liquid cooling systems, fuel of fuel cells, or blood ofartificial hearts, etc.

Referring to FIG. 2, FIG. 2 illustrates an exploded diagram of theultra-thin miniature pump according to the first exemplary embodiment ofthe present invention. As shown in FIG. 2, the ultra-thin miniature pump10 according to the first exemplary embodiment of the present inventioncomprises a main body 12, a rotor 14, and a stator 16. The main body 12includes a cover part 18 and a bottom part 20. Therein, a joint surface22 between the cover part 18 and the bottom part 20 possesses ananti-leakage device, such as an O-ring gasket 24 which is disposed in agroove 26 between the cover part 18 and the bottom part 20 of the firstembodiment. A plurality of screws 28 are utilized to bolt and fix thecover part 18 and the bottom part 20, and then the O-ring gasket 24 iscompressed to keep an anti-leakage condition of the main body 12.Furthermore, a chamber (not shown in FIG. 2) including a suction port 30and a discharge port 32 is formed inside the main body 12, and thesuction port 30 and the discharge port 32 are disposed in a side of thecover part 18. The bottom part 20 includes a fixed base 34, and abearing 36, such as an oil-free lubrication bearing, is disposed in thefixed base 34. It is noted that the suction port 30 and the dischargeport 32 are not restricted to be disposed in the cover part 18. In otherembodiments, the suction port 30 and the discharge port 32 may bedisposed in the bottom part 20 depending on various designs. Moreover,the fixed base 34 is not restricted to be disposed in the bottom part20. In other embodiments, the fixed base 34 may be disposed in the coverpart 18 depending on various designs, or the fixed base 34 may bedisposed in both of the cover part 18 and the bottom part 20.

As shown in FIG. 2, the rotor 14 is disposed in the chamber, and itincludes a magnet set 38, an impeller 40, and a central shaft 42.Therein, the magnet set 38 could be an annular magnet, and the annularmagnet is fixed on a downward surface (not shown in FIG. 2) of theimpeller 40 and located between the plurality of vanes 44 of theimpeller 40 and the central shaft 42. The downward surface of theimpeller 40 includes an annular cavity (not shown in FIG. 2) locatedbetween the vanes 44 of the impeller 40 and the central shaft 42, andthe annular magnet is corresponding to the annular cavity and fixed inthe annular cavity by adhering or embedding. Moreover, the central shaft42 is connected to the bearing 36, which is disposed in the fixed base34, for rotating, and the impeller 40 with the magnet set 38 areconnected to the central shaft 42 and aligned by the central shaft 42.Then, the impeller 40 and the magnet set 38 rotate in coaxial manner.

As shown in FIG. 2, the stator 16 is disposed inside a cavity 46 of thechamber in the bottom part 20, and it includes a plurality of coils 48corresponding to the magnet set 38 axially and a substrate 50 fordisposing the coils 48. Therein, the coils 48 and the magnet set 38generate an axial magnetic flux to make the impeller 40 rotate fortransporting the fluid from the suction port 30 to the discharge port32. It is noted that the magnet set 38 may include a plurality ofmagnets, and the magnets are corresponding to the coils 48 respectivelyand fixed on the downward surface of the impeller 40.

As shown in FIG. 2, the main body 12 further includes at least anopening (not shown in FIG. 2), and the coils 48 are electricallyconnected outside of the main body 12 through the opening. Furthermore,a sealing layer (not shown in FIG. 2) covers the cavity 46 to seal thecoils 48 and the opening to prevent the fluid from leaking through theopening, and the fluid and the coils 48 are isolated by the sealinglayer. Moreover, there is a stripper (not shown in FIG. 2) disposedbetween an inside wall of the main body 12 and the impeller 40. Thestripper is an isolating wall located between the suction port 30 andthe discharge port 32 to prevent the pressurized fluid in the outletregion(not shown in FIG. 2) from flowing into the inlet region(not shownin FIG. 2) at low pressure. The ultra-thin miniature pump 10 of thepresent invention utilizes a driver (not shown in FIG. 2), which isdisposed outside of the main body 12 or on the substrate 50, to make thecoils 48 generate an axial magnetic flux, and then the axial magneticflux make the magnet set 38, which is connected on the impeller 40,rotate for transporting the fluid from the suction port 30 to thedischarge port 32.

Referring to FIG. 3, FIG. 3 illustrates an exploded diagram of anultra-thin miniature pump according to a second exemplary embodiment ofthe present invention. As shown in FIG. 3, an ultra-thin miniature pump60 according to a second exemplary embodiment of the present inventionis utilized to transport a fluid (not shown in FIG. 3), and it comprisesa main body 62, a rotor 64, a stator 66, and a sealing layer (not shownin FIG. 3).

As shown in FIG. 3, the main body 62 includes a cover part 68, a bodypart 70, and a bottom part 72. Therein, a joint surface 74 between thecover part 68 and the body part 70 possesses an anti-leakage device,such as an O-ring gasket 76 which is disposed in a groove 78 between thecover part 68 and the body part 70 of the present embodiment. Aplurality of screws 80 are utilized to bolt and fix the cover part 68,the body part 70, and the bottom part 72, and then the O-ring gasket 76is compressed to keep an anti-leakage condition of the main body 62.Furthermore, a chamber (not shown in FIG. 3) including a suction port 82and a discharge port 84 is formed inside the main body 62, and thesuction port 82 and the discharge port 84 are disposed in a side of thecover part 68. The bottom part 72 includes a fixed base 86, and abearing 88, such as an oil-free lubrication bearing, is disposed in thefixed base 86. It is noted that the suction port 82 and the dischargeport 84 are not restricted to be disposed in the cover part 68. In otherembodiments, the suction port 82 and the discharge port 84 may bedisposed in the body part 70 depending on various designs. Moreover, thefixed base 86 is not restricted to be disposed in bottom part 72. Inother embodiments, the fixed base 86 may be disposed in the cover part68 depending on various designs, or the fixed base 86 may be disposed inboth of the cover part 68 and the bottom part 72.

As shown in FIG. 3, the rotor 64 is disposed in the chamber, and itincludes a magnet set 90, an impeller 92, and a central shaft 94.Therein, the magnet set 90 could be an annular magnet, and the annularmagnet is fixed on a downward surface (not shown in FIG. 3) of theimpeller 92 and located between the plurality of vanes 96 of theimpeller 92 and the central shaft 94. The downward surface of theimpeller 92 includes an annular cavity (not shown in FIG. 3) locatedbetween the vanes 96 of the impeller 92 and the central shaft 94, andthe annular magnet is corresponding to the annular cavity and fixed inthe annular cavity by adhering or embedding. Moreover, the central shaft94 is connected to the bearing 88, which is disposed in the fixed base86, for rotating, and the impeller 92 with the magnet set 90 areconnected to the central shaft 94 and aligned by the central shaft 94.Then, the impeller 92 and the magnet set 90 rotate in coaxial manner.

As shown in FIG. 3, the stator 66 is disposed inside a cavity 98 of thechamber in the body part 70 and the bottom part 72, and it includes aplurality of coils 100 corresponding to the magnet set 90 axially and asubstrate 102 for disposing the coils 100. Therein, the coils 100 andthe magnet set 90 generate an axial magnetic flux to make the impeller92 rotate for transporting the fluid from the suction port 82 to thedischarge port 84. It is noted that the magnet set 90 may include aplurality of magnets, and the magnets are corresponding to the coils 100respectively and fixed on the downward surface of the impeller 92.

As shown in FIG. 3, the main body 62 further includes at least anopening 104 disposed in the bottom part 72, and the coils 100 areelectrically connected outside of the main body 62 through the opening104. The opening 104 is not restricted to be disposed in the bottom part72. In other embodiment, the opening 104 may be disposed in a side ofthe body part 70.

As shown in FIG. 3, the sealing layer is located in a portion of thechamber of the body part 70 and the bottom part 72 and it covers thecavity 98 to seal the coils 100 and the opening 104 to prevent the fluidfrom leaking through the opening 104 and a joint surface 106 between thebody part 70 and the bottom part 72, and the fluid and the coils 100 areisolated by the sealing layer. Moreover, there is a stripper (not shownin FIG. 3) disposed between an inside wall of the main body 62 and theimpeller 92. The stripper is an isolating wall located between thesuction port 82 and the discharge port 84 to prevent the pressurizedfluid in the outlet region(not shown in FIG. 3) from flowing into theinlet region(not shown in FIG. 3) at low pressure. The ultra-thinminiature pump 60 of the present invention utilizes a driver (not shownin FIG. 3), which is disposed outside of the main body 62 or on thesubstrate 102, to make the coils 100 generate an axial magnetic flux,and then the axial magnetic flux make the magnet set 90, which isconnected on the impeller 92, rotate for transporting the fluid from thesuction port 82 to the discharge port 84.

Compared to the prior art, the ultra-thin miniature pump of the presentinvention utilizes a design of axial magnetic flux. Since the magnet setis integrated with the impeller and the coils are axially aligned withthe magnet set, the ultra-thin miniature pump of the present inventionis light in weight and compact in size. Furthermore, since the magnetset is designed according to the shape of impeller of vortex pumps,there is more space for a motor of the ultra-thin miniature pump toincrease its diameter and then the rotating torque and the head rise ofthe pump are promoted. Moreover, since the motor has larger dissipationspace, it will prevent the motor from overheating and increase thelifetime of the motor.

1. An ultra-thin miniature pump, which is applied to transport a fluid,comprising: a main body including a cover part and a bottom part,wherein a joint surface between the cover part and the bottom partpossesses an anti-leakage device, and a chamber including a suction portand a discharge port is disposed inside the main body; a rotor beingdisposed in the chamber and including a magnet set, an impeller, and acentral shaft, wherein the magnet set is connected on a surface of theimpeller, and the impeller and the magnet set are aligned by the centralshaft and rotate in coaxial manner; and a stator being disposed in thechamber and including a plurality of coils corresponding to the magnetset axially, wherein the coils and the magnet set generate an axialmagnetic flux to make the impeller rotate for transporting the fluidfrom the suction port to the discharge port.
 2. The ultra-thin miniaturepump as claimed in claim 1, wherein the cover part includes a fixed baseand a bearing disposed in the fixed base, and the central shaft isconnected to the bearing for rotating.
 3. The ultra-thin miniature pumpas claimed in claim 1, wherein the bottom part includes a fixed base anda bearing disposed in the fixed base, and the central shaft is connectedto the bearing for rotating.
 4. The ultra-thin miniature pump as claimedin claim 1, wherein the anti-leakage device is a gasket which isdisposed between the cover part and the bottom part.
 5. The ultra-thinminiature pump as claimed in claim 1, wherein the magnet set is anannular magnet, and the annular magnet is fixed on the surface of theimpeller and located between a plurality of vanes of the impeller andthe central shaft.
 6. The ultra-thin miniature pump as claimed in claim5, wherein the surface of the impeller includes an annular cavitylocated between the vanes of the impeller and the central shaft, and theannular magnet is corresponding to the annular cavity and fixed therein.7. The ultra-thin miniature pump as claimed in claim 1, wherein themagnet set includes a plurality of magnets, and the magnets arecorresponding to the coils respectively and fixed on the surface of theimpeller.
 8. The ultra-thin miniature pump as claimed in claim 1,wherein the coils are sealed by a sealing layer.
 9. The ultra-thinminiature pump as claimed in claim 8, wherein the main body furtherincludes at least an opening, the coils electrically connect outside ofthe main body, and the coils and the opening are sealed by the sealinglayer.
 10. The ultra-thin miniature pump as claimed in claim 1, whereina stripper is disposed between an inside wall of the main body and theimpeller, and the stripper is located between the suction port and thedischarge port to prevent a pressurized fluid in an outlet region fromflowing into an inlet region at low pressure.
 11. An ultra-thinminiature pump, which is applied to transport a fluid, comprising: amain body including a cover part, a body part, and a bottom partcombined in sequence, wherein a joint surface between the cover part andthe body part possesses an anti-leakage device, and a chamber includinga suction port and a discharge port is formed inside the main body; arotor being disposed in the chamber and including a magnet set, animpeller, and a central shaft, wherein the magnet set is connected on asurface of the impeller, and the impeller and the magnet set are alignedby the central shaft and rotate in coaxial manner; a stator beingdisposed in the chamber of the body part and the bottom part andincluding a plurality of coils corresponding to the magnet set axially,wherein the coils and the magnet set generate an axial magnetic flux tomake the impeller rotate for transporting the fluid from the suctionport to the discharge port; and a sealing layer located in a portion ofthe chamber of the body part and the bottom part for sealing the coilsand preventing the fluid from leaking through a joint surface betweenthe body part and the bottom part.
 12. The ultra-thin miniature pump asclaimed in claim 11, wherein the cover part includes a fixed base and abearing disposed in the fixed base, and the central shaft is connectedto the bearing for rotating.
 13. The ultra-thin miniature pump asclaimed in claim 11, wherein the bottom part includes a fixed base and abearing disposed in the fixed base, and the central shaft is connectedto the bearing for rotating.
 14. The ultra-thin miniature pump asclaimed in claim 11, wherein the anti-leakage device is a gasket whichis disposed between the cover part and the body part.
 15. The ultra-thinminiature pump as claimed in claim 11, wherein the magnet set is anannular magnet, and the annular magnet is fixed on the surface of theimpeller and located between a plurality of vanes of the impeller andthe central shaft.
 16. The ultra-thin miniature pump as claimed in claim15, wherein the surface of the impeller includes an annular cavitylocated between the vanes of the impeller and the central shaft, and theannular magnet is corresponding to the annular cavity and fixed in theannular cavity.
 17. The ultra-thin miniature pump as claimed in claim11, wherein the magnet set includes a plurality of magnets, and themagnets are corresponding to the coils respectively and fixed on thesurface of the impeller.
 18. The ultra-thin miniature pump as claimed inclaim 11, wherein the main body further includes at least an opening,the coils electrically connect outside of the main body, and the coilsand the opening are sealed by the sealing layer.
 19. The ultra-thinminiature pump as claimed in claim 11, wherein a stripper is disposedbetween an inside wall of the main body and the impeller, and thestripper is located between the suction port and the discharge port toprevent a pressurized fluid in an outlet region from flowing into aninlet region at low pressure.